How do Rechargeable Batteries Work?

They're great for the environment, but how do rechargeable batteries work? Typical rechargeable batteries can be renewed hundreds of times. So, the initial higher cost of rechargeable batteries is quickly offset by the fact that one battery can last for several years.

How Do Rechargeable Batteries Work Their Magic?
Rechargeable batteries have been around for 150 years. In 1859 Gaston Plante, a French physicist, invented the lead-acid battery. This rechargeable battery is still used today as the standard electrical source in most gasoline-powered cars. Modern rechargeable batteries are used today to power everything from toys to lap to computers. Here's how they work:

• Start with the basics. A normal battery (called a primary battery) produces electricity using an electrochemical reaction. This reaction causes electrons to flow from one electrode (metal rod) to another through an electrolyte (a liquid or solid chemical substance). The negative (-) and positive (+) terminals on a battery provide an outlet and inlet for the electrons to flow. In practice, electrical wires are connected to the terminals and electricity (in the form of electrons) flows through the wires, powering the device connected to the battery's terminals. Primary batteries lose their effectiveness as the chemical materials break down and the energy of the reactions fades.
• Now reserve everything. In a rechargeable battery (called a secondary battery), applying an electrical charge to the battery reverses the chemical reactions that take place. The reversed electron flow restores the chemical elements involved to their original form and the battery is ready to begin the process again.
• Types of rechargeable batteries. Although Plante's lead/acid batteries were the first type of rechargeable battery, there are several types of rechargeable batteries on the market today. Nickel Cadmium (NiCad) batteries were an early form of portable rechargeable battery, but they contain toxic chemicals and have been replaced by other forms. Nickel-Metal Hydride Battery (NiMH) were first developed in the 1980s and produce energy more efficiently than NiCad batteries. Lithium-ion Battery (Li-ion) batteries are very efficient and have a longer shelf life than NiMH batteries.